| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 33°F | 54°F | 43°F | 4.1" |
| February | 35°F | 57°F | 45°F | 4.0" |
| March | 43°F | 67°F | 54°F | 4.2" |
| April | 51°F | 75°F | 63°F | 4.1" |
| May | 59°F | 82°F | 70°F | 3.8" |
| June | 67°F | 90°F | 78°F | 3.6" |
| July | 70°F | 91°F | 79°F | 3.9" |
| August | 70°F | 90°F | 79°F | 4.7" |
| September | 64°F | 84°F | 73°F | 4.6" |
| October | 51°F | 75°F | 62°F | 3.4" |
| November | 40°F | 65°F | 52°F | 3.5" |
| December | 38°F | 58°F | 47°F | 5.1" |
| Index | Roswell | Georgia | National |
| Air quality index | 52 | 41 | 42 |
| Pollution index | 19,982,200 | 1,874,972 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 162 |
| Days with moderate air quality | 184 |
| Days w/ poor A.Q. for sensitive groups | 18 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.210% |
| Benzene | 0.260% |
| Carbon Tetrachloride | 0.050% |
| Lead | 0.100% |
| Mercury | 0.010% |
| City | Population | Air Quality Index | National Avg. |
| Cumming, GA | 6,528 | 37 | 26.0% |
| Marietta, GA | 60,687 | 52 | 4.0% |
| Dunwoody, GA | 49,466 | 52 | 4.0% |
| Vinings, GA | 12,546 | 52 | 4.0% |
| Norcross, GA | 16,876 | 52 | 4.0% |
| Roswell, GA | 94,884 | 52 | 4.0% |
| City | Population | Air Quality Index | National Avg. |
| South Gate, CA | 94,905 | 72 | 44.0% |
| Portsmouth, VA | 94,961 | 40 | 20.0% |
| North Vancouver, BC | 94,662 | n/a | |
| Sunrise, FL | 94,657 | 41 | 18.0% |
| Hesperia, CA | 95,163 | 89 | 78.0% |
| Roswell, GA | 94,884 | 52 | 4.0% |
Here are the best places to live in Georgia
Top 10 best public schools in Roswell
10 best cities to buy a new house in Georgia
These are the 10 most affordable cities in Georgia